One of the most desired critical and life-saving technologies in combat zones and field operations is reliable detection of on-road or off-road Improvised Explosive Devices (IEDs), Explosively Formed Penetrators (EFPs) and hidden weapon caches. IEDs, roadside bombs, and suicide car bombs, have caused over 60% of all American combat casualties in Iraq and 50% of combat casualties in Afghanistan. To combat such threats, a widespread video surveillance system could be used. However, the required infrastructure and the large installation costs of such a massive video surveillance system in the typically remote and underdeveloped areas subject to combat has prevented any widescale implementation of such systems. In contrast, RF sensing technology has the potential to defeat the IED threat by monitor movements and disturbances to areas of suspected IED activity. While optical surveillance systems fail to effectively operate in darkness or harsh weather conditions, RF sensors have the benefit of all-weather day and night operation.
The application of RF technology for detection of buried targets will typically use an RF transmitter that sends electromagnetic pulses to the area under interrogation and a sensitive receiver to collect the reflections. The amplitude and phase information in the reflected signal is extracted and processed in real-time or offline to determine the signature of a suspicious target. Although advanced imaging radars have been developed to detect and image buried or hidden-behind-wall targets, such radars will generally need to be scanned across the area of interest to image their targets and can be relatively expensive due to their sophisticated signal processing.
Accordingly, there is a need in the art for low-cost RF-based systems that can detect threats such as IEDs.